1. Field of the Invention
The present invention relates to mobile information processing apparatus such as notebook computer, mobile information processing apparatus cover, and desktop information processing apparatus such as desktop computer.
2. Background Arts
As a result of pursuing for a small-sized mobile information processing apparatus of recent years, much of the mobile information processing apparatus nowadays spreads heat from a surface of its main body having installed a heat-generating CPU (Central Processing Unit). However, in accordance to a progress being made on a high-speed CPU, an amount of heat generated from the CPU will also increase extensively, which leaves us with a problem of how to improve efficiency of heat spreading.
FIG. 11 illustrates a side view of conventional mobile information processing apparatus disclosed in Japanese unexamined patent publication HEI 8-261672. In the conventional mobile information processing apparatus, the amount of heat generated from the main body installing CPU is several times larger than an amount of heat released from a display unit provided with a screen display. In spite of this, outer surface areas of the main body and the display unit are approximately equal. Attending to this fact, the conventional mobile information processing apparatus has improved an efficiency of heat spreading by transferring the heat generated at the main body to the display unit, so that the transferred heat is also released from the outer surface of the display unit.
Description of the numbered components in the drawing of FIG. 11 follows: a main body 401 of the mobile information processing apparatus where a keyboard 402 is being placed on at an inner surface of the main body 401; a circuit board 403 installed at the main body 401 where a CPU 404 is mounted on; a heat collecting board 405 mounted on a top surface of the CPU 404; a display unit 406 of the mobile information processing apparatus; a liquid crystal display panel 407 placed at an inner surface of the display unit 406; a heat spreading board 408 mounted on an external surface of the display unit 406; a connecting unit 409 that connects the main body 401 and the display unit 406; a hinge 410 situated inside the connecting unit 409 and above the main body 401; a first heat pipe 411 installed at the main body 401; and a second heat pipe 412 installed at the display unit 406. The first heat pipe 411 and the second heat pipe 412 are connected at the hinge 410 via a rotating circular plate. The circular plate rotates when the display unit 406 is being closed on top of the main body 401.
The heat generated at the main body 401 is transferred to the display unit 406 through the first heat pipe 411 and the second heat pipe 412. The heat pipes cause to a complexity of an internal structure of the conventional mobile information processing apparatus. In addition, the heat pipes must be incorporated from an early stage of designing. Therefore, the heat pipes have a problem such as unable to deal with a grade-up of the CPU and unable to use a PC card that has an unexpected electricity consumption.
At the same time, since a ground line and a signal line that electrically connects the main body 401 and the display unit 406 must pass through a narrow space in vicinity of the connecting unit 409 through the hinge 410, because of this the ground line and the signal line should be made thin. The thin lines lacks in firm electronic connection and this may cause an occurrence of blur in the display panel, and further, with a repeated opening and closing of the display unit 406 the lines may be cut off.
In many cases, a cover is placed over the mobile information processing apparatus for reasons such as absorbing shock from outside, viewpoint of design, and easy carrying. Japanese unexamined utility model publication HEI 4-3126 discloses a conventional book type cover for the mobile information processing apparatus.
FIGS. 12 and 13 illustrate the book type cover for the conventional mobile information processing apparatus. FIG. 12 is an external view of the mobile type information processing apparatus covered by the book type cover when the display unit is being closed. FIG. 13 is the external view of the mobile information processing apparatus covered by the book type cover when the display unit is being opened.
Description of the numbered components in the drawings follows: a mobile type information processing apparatus 501 comprising a main body 502 and a display unit 503; the book type cover for the mobile information processing apparatus 601 comprising of two parts including a part that covers the main body 502 and a part that covers the display unit 503 of the mobile information processing apparatus; straps 602 which bring together the cover 601 with the main body 502 and the display unit 503; a handle 603 attached to the cover 601; and shoulder strap rings 604 attached to the cover 601.
However, this type of cover includes no means to deal with heat, so when the cover is being used to cover the mobile type information processing apparatus that spreads heat from the outer surface of the main body, the heat cannot sufficiently be released from the outer surface due to this kind of cover. This kind of cover causes a problem of increased temperature inside the main body of the mobile information processing apparatus.